A. (30%) light sources a. (3%) What is the major advantage to have I2 in the envelop of tungsten lamps? (i.e., the advantage of tungsten/halogen lamps) b. (4%) Why is D2-lamp a continuum source rather than a line source at 200~350 nm? c. (5%) Draw the scheme diagram of HCL. Indicate the names of the necessary part. Which part of the device is "hollow" and why is "hollow" necessary? d. (4%) Why is the emission of glow discharge analogue to HCL? (i.e., describe their similarity) e. (6%) List 3 steps (mechanism) that generate Lasers. (不必说明) f. (8%) Describe the criteria for excited molecules to emit coherent radiation. B. (18%) FT-IR & FT-Raman a. (6%) Draw a scheme diagram of Michelson interferometer with the necessary parts. Describe the function of each part. b. (4 %) In practice, does an FTIR use a monochromatic source or a continuum source? Why so? (or why not?) c. (2 %) (i) In practice, does an FT-Raman use a monochromatic light source or a continuum light source? (6%) (ii) Before the light path enters the interferometer, is it monochromatic or polychromatic? Why so? C. (15 %) monochromator & detectors a. (5 %) Why is high resolution, in general, unnecessary for solution-phase UV/Vis experiments? b. (5 %) A spectrum has a S/N ratio of 8/1. How many spectra must be averaged to increase the S/N ratio to 20/1? (列出式子，不要计算) c. (5%) Why is it most accurate to measure the absorbance in the range of A = 0.4~0.9? D. (21 %) Answer the following questions concisely (i.e., short and clear).a. (7%) Describe the mechanism of Smith-Hieftje method. Please focus on how this method can correct the background. b. (6 %) Echellette and Echelle gratings (i) Describe the difference between their structures and (ii) Whose resolution is better? How so? (hint: what should be placed in between the grating and detector?) c. (4%) Please explain the reason why the ionization interference is not serious in ICP-OES. d. (4%) Please define "charge coupled device". E. (22 %) multiple choices (单或多选题 & 简答， 错一个答案，倒扣一分；先读问题再看选项) We have introduced the following types of devices in class: a. Lasers b. D2 lamp c. tungsten lamp d. HCLs e. electrodeless dischrage lamp f. prism g. echelle grating h. echellette grating i. concave diffraction grating j. interference filters k. absorption filters l. interferometer m. phototube n. photodiode o. photodiode array p. photomultiplier tube q. photoconductor (MCT) r. charge coupled devices s. thermocouple (DTGS) t. laminar flow burner u. ICP torch v. electrothermal atomizer w. arc and spark plasma sources x. ATR y. demountable gas cell for IR z. gas cell with known amount of reference materials aa. KBr pellets a. (4 %) What types of transducers might have the best sensitivity? b. (12 %) From the list above, select the necessary devices to quantify NOx ( 汽车排放的废气种类之一) for street cars. (You are welcome to write or explain the purpose of your choice.) c. (6 %) In your experimental and instrumental design, do you use "internal standard" or "standard addition"? Why so? (要记得说明原因) --

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